1. Field of the Invention
The present invention relates to a rechargeable battery, and more particularly, to a rechargeable battery with a pouch type external case.
2. Description of the Related Art
Rechargeable batteries can be charged and discharged unlike primary batteries which cannot be recharged. Low-capacity rechargeable batteries are used for portable compact electronic apparatuses such as mobile phones or notebook computers and camcorders and large-capacity rechargeable batteries are widely used as a power supply for driving a motor of a hybrid vehicle, a power storage battery, and the like.
The rechargeable batteries include an electrode assembly which includes a positive electrode, a negative electrode, and a separator, and a case having the electrode assembly positioned therein. The rechargeable batteries may be classified into a circular type, an angular type, and a pouch type depending on their shapes.
Among them, the pouch-type rechargeable battery has a structure in which the electrode assembly is incorporated in a pouch-shaped case and sealed. Therefore, due to the structure of the pouch-type rechargeable battery, it is difficult to refill or exchange an electrolyte solution after injecting the electrolyte solution at the time of manufacturing the battery. As a result, even when an injection error of the electrolyte solution occurs during using the pouch-type rechargeable battery, reworking is not practical and even when a life-span of the battery is shortened due to the depletion of the electrolyte solution, the generation of gas, and the like, regeneration is also not practical. In particular, such a structural limit may be a problem when the pouch-type rechargeable battery is used as the large-capacity battery.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.